1. Field of the Invention
The invention relates to a resistor and a manufacturing method thereof, and more particularly, to a resistor and a method of manufacturing a resistor integrated with a transistor having metal gate.
2. Description of the Prior Art
To increase the performance of transistors, metal gates are prevalently used in the semiconductor field: the metal gates competent to the high dielectric constant (high-k) gate dielectric layer are used to replace the traditional polysilicon gates to be the control electrode. The metal gate approach can be categorized to the gate first process and the gate last process. And the gate last process gradually replaces the gate first process because a range of material choices for the high-k gate dielectric layer and the metal gate are expanded.
Additionally, resistors are elements which are often used for providing regulated voltage and for filtering noise in a circuit. The resistors generally include polysilicon and silicide layers.
In the current semiconductor field, though the fabricating processes are improved with the aim of reaching high yields, it is found that integration of the manufacturing methods of those different kinds of semiconductor devices is very complicated and difficult. Therefore, a method for fabricating a resistor integrated with a transistor having metal gate is still in need.